Seedbox

The common name “Seedbox” refers to these unusual, cube-shaped seedpods

The cute little square seed pods of Ludwigia alternifolia, or Seedbox, are drying now in winter fields along with other stars of summer, like Queen Anne’s Lace and Ironweed. When fully dry, the hard seeds inside these boxes will rattle when shaken, giving rise to another common name, Rattlebox.

This dainty member of the evening primrose family has 4-petalled, bright yellow flowers that are only a half inchin diameter and sprout from the leaf axils. Four prominent sepals are visible behind the circular petals, as you can see in the photo below. Compare the size of this flower to the 2-inch yellow flowers of Sundrops, or Common Evening Primrose.

Four rounded, yellow petals and four large sepals

The leaves of Seedbox are alternate, entire, narrowly lanceolate, and pointed. The plant is much-branched, and grows 3 to 4 feet in height. You’ll find it blooming summer through fall; it prefers damp habitat, like marshes, seeps, and other wet areas.

The plants in the gallery below were found growing at the base of Brush Mountain in August. The seedpods were photographed later in late November. Plants growing nearby included Cardinal Flower, Blue Lobelia, and Swamp Milkweed, all plants that prefer to keep their feet wet.

Seedbox: leaves, stems, flowers

The flowers at the top of the plant have lost their yellow petals

The square seed box can be seen at the center; it will enlarge and then dry out to form a cube-shaped box

The petals fall off easily, revealing the sepals

The cube-shaped seedpods of Seedbox

The tiny seeds pour out of the hole at the top of the box

I love this shape!

Seedbox

Seedbox

The boxes rattle when shaken; the seeds sprinkle out of the small hole at the top